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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

21206 results found.

  1. GRB990123, OSSE observations
  2. GRB990123: NIR Observation
  3. "GRB 990123: New BV Observations"
  4. GRB 990123: New Optical Observations, Decay Measure
  5. GRB 990123 Optical Follow-Up
  6. GRB 990123: Possible Gravitationally Lensed Burst?
  7. GRB990123, optical observation
  8. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  9. GRB 990123 r-band photometry
  10. GRB 990123 Optical Follow-up
  11. GRB990123, early optical counterpart detection
  12. GRB 990123, Radio observations
  13. GRB990123, BeppoSAX WFC detection and NFI planned follow-up
  14. Possible identification of SN1999E with GRB980910
  15. Optical Observations of GRB 981220
  16. GRB 981226: radio variable
  17. GRB 981226 Optical Observations
  18. GRB981226 BeppoSAX follow up
  19. GRB 981226
  20. GRB 981226 optical observations
  21. GRB981220 B, R and I band observations
  22. GRB 981220:Optical Observations
  23. GRB 981226 optical observations
  24. GRB 981220, radio observations
  25. GRB 981220: BeppoSAX/GRBM results
  26. GRB981220 Optical Observations
  27. GRB 981220
  28. GRB 980326/Host Galaxy
  29. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  30. BeppoSAX NFI Observation of GRB980425
  31. GRB980329 R,I flux calibration and R,I,K upper limits
  32. GRB980425 Optical Follow-up
  33. GRB980425: X-ray revised positions
  34. GRB980703 Very Long Baseline Interferometry
  35. GRB970508 optical observations
  36. GRB980519, Optical Observations
  37. GRB980703 - BeppoSAX/GRBM detection
  38. GRB980703 optical photometry
  39. GRB 980703: BATSE Observations
  40. GRB980703 optical observations
  41. GRB980703: Radio transient
  42. GRB980703 Transient Optical Follow-Up
  43. GRB980703: LOTIS observation at early times
  44. GRB980613 Optical Observations
  45. GRB 980703
  46. BeppoSAX NFI observations of GRB 980703
  47. GRB980703 optical followup
  48. Radio observations of SGRs
  49. SGR1900+14 field optical observations
  50. GRB 980613: Optical transient and its host galaxy
  51. SGR1627-41, RXTE/ASM observations
  52. GRB 980613: Detection of the probable host galaxy
  53. GRB 980613 Optical Observations
  54. GRB 980613 optical observations
  55. Discovery of a new SGR source, SGR1627-41
  56. GRB980613 Optical Observations
  57. GRB980613 observations from Palomar
  58. GRB980613 Near Infra-Red Observations
  59. GRB980613, BeppoSAX WFC positions
  60. GRB971214 Secondary Standards
  61. GRB980519 Secondary Standards
  62. GRB 980519 Optical Observations
  63. GRB 980519
  64. GRB980519 optical observations
  65. GRB 980519 Optical Observations
  66. GRB980519 BATSE Observations
  67. GRB970519, optical follow-up at Schmidt Calern
  68. GRB980519 Optical Observations
  69. GRB 980519 Optical Observations
  70. GRB980515, BeppoSAX IAUC to be submitted
  71. GRB980519, BeppoSAX-WFC position
  72. BeppoSAX GRB ALERT: updated position of grb980515
  73. GRB 980425 Brightness Temperature
  74. BSAX Observations of GRB980425 field
  75. SAX J0840.7+2248 Optical Observations
  76. GRB980425: optical obs.
  77. GRB980425: Radio Observations
  78. report on BSAX observations of GRB980425
  79. GRB980326 X-ray Observations
  80. GRB980326, optical observations
  81. GRB980326, optical observations
  82. GRB980329 Keck K-band observations
  83. GRB980329 sub-millimeter observations
  84. GRB980326 optical observations
  85. GRB980329 optical observations
  86. GRB980329 VLA observations
  87. GRB980329 optical observations
  88. GRB980326 optical observations
  89. Optical Observations of GRB 970508
  90. GRB 971214: Redshift from Keck Observations
  91. Near-IR follow-up on GRB 971227
  92. Optical Observations of the GRB 971227 field
  93. Optical Observations on GRB 971227
  94. GRB971227: Plaskett R-band observations
  95. GRB 971227: Optical clarifications
  96. GRB971227: Further CAHA R-band images
  97. GRB971227: LOTIS observations
  98. GRB971214: Optical Observations and Calibrations
  99. Sub-millimeter Observations of GRB 971214 at the JCMT
  100. GRB 971214: KPNO Optical Observations

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